The focus of this project is to improve the diagnosis and treatment of fetal disease. Focus is placed on the prenatal diagnosis of congenital anomalies with non-invasive methods (e.g., high resolution ultrasound and color Doppler flow mapping) and invasive methods. The Branch pioneered the utilization of thin-gauge endoscopy in the diagnosis of fetal congenital anomalies and endoscopic fetal surgery for the treatment of disorders of multiple gestation ( Twin Reversal Arterial Perfusion Sequence; TRAP) and fetal obstructive uropathy. This year the Branch reported its experience in the utilization of percutaneous umbilical cord ligation in the management of monochorionic multiple gestations with complications such as the "twin to twin transfusion syndrome" and TRAP sequence. Fifteen patients were referred to evaluation and possible treatment. Two were excluded because of misdiagnosis. Of the remaining patients there were 10 with TRAP sequence, one discordant twin with acrania and 2 cases with twin to twin syndrome with a hydropic twin. All cases were evaluated at Hutzel Hospital /Wayne State University where they were referred for treatment. Umbilical cord ligation was performed with a combined endoscopic and sonographic approach in 11 of 13 cases ( 84 % of cases). An average of 8 weeks was gained after the procedure. Seven of the 11 patients undergoing cord ligation had a living child. Endoscopic devascularization of a large chorioangioma of the placenta was also accomplished endoscopically for the first time. Chorioangiomas are hamartomas which occur in 1 % of placentas. Large chorioangiomas have been associated with severe complications often related to a high output fetal cardiac failure . These complications include polyhydramnios, non-immune hydrops, cardiomegaly, growth retardation, preterm labor and fetal death ( 16 %). Maternal complications include toxemia, abruption placenta and fetal-maternal transfusion. A patient with a large chorioangioma and severe cardiac failure was referred to Hutzel Hospital/Wayne State University at 24 weeks gestation. The fetus was critically ill with signs of impeding fetal death (i.e. reversal of flow in the ductus venosus). Endoscopic ligation of the vessel was accomplished successfully but the fetus died in the third post-operative day. This case illustrates the feasibility of performing this surgical procedure with minimally invasive surgery and opens the possibility that early identification and treatment before fetal cardiac failure may be life-saving.